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Thread-Topic: Proposal: short_var_export($value, bool $return=false, int
 $flags=0)
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Date: Mon, 18 Jan 2021 21:12:01 +0000
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Subject: Proposal: short_var_export($value, bool $return=false, int $flags=0)
From: tysonandre775@hotmail.com (tyson andre)

Hi=A0internals,=0A=
=0A=
I've created a PR https://github.com/php/php-src/pull/6619 to add an altern=
ative to var_export().=0A=
The proposed short_var_export() also outputs/returns a parseable representa=
tion of a variable,=0A=
but adds requested features for var_export.=0A=
=0A=
1. Use `null` instead of `NULL` - the former is recommended by more coding=
=0A=
   guidelines (https://www.php-fig.org/psr/psr-2/).=0A=
2. Change the way indentation is done for arrays/objects.=0A=
   See ext/standard/tests/general_functions/short_var_export1.phpt=0A=
   (e.g. always indent with 2 spaces, never 3 in objects, and put the array=
 start on the=0A=
   same line as the key)=0A=
3. Render lists as `"[\n  'item1',\n]"` rather than `"array(\n  0 =3D> 'ite=
m1',\n)"`=0A=
4. Prepend `\` to class names so that generated code snippets can be used i=
n=0A=
   namespaces (e.g. with eval()) without any issues.=0A=
5. Support opt-in `SHORT_VAR_EXPORT_SINGLE_LINE` in `int $flags`.=0A=
   This will use a single-line representation for arrays/objects, though=0A=
   strings with embedded newlines will still cause newlines in the output.=
=0A=
   (`"['item']"`)=0A=
=0A=
Changing var_export() itself has been proposed 9 months ago (https://extern=
als.io/message/109415) =0A=
but the RFC discussion seems to be on hold.=0A=
https://externals.io/message/106674#106684 suggested adding a new function =
as an alternative.=0A=
One of the major objections is that changing var_export() (instead of addin=
g a new function) would have these drawbacks:=0A=
=0A=
1. It would be impractical to backport/polyfill calls with 3 args to older =
php versions, if `int $flags` was added.=0A=
   ArgumentCountErrors are thrown in php 8.0 for too many parameters, and e=
arlier php versions warn=0A=
2. If defaults were changed, then thousands of unit tests in php-src and ot=
her projects may fail due to=0A=
   tests expecting the exact representation of a variable, requiring a lot =
of work to update tests=0A=
=0A=
I feel like the user-friendliness of the enhancements makes adding another =
function=0A=
to PHP worth it. (e.g. copying short_var_export() into a code snippet such =
as the expectation for a unit test or a configuration)=0A=
I don't believe I've seen an RFC for a separate function before.=0A=
=0A=
Also, a native C implementation would be much more efficient than a polyfil=
l implemented in PHP,=0A=
e.g. https://github.com/brick/varexporter/issues/14=0A=
=0A=
I plan to start an RFC document shortly. Thoughts?=0A=
(e.g. for the name, short_var_export() seemed more appropriate than var_exp=
ort_short(), pretty_var_export() or canonical_var_export())=0A=
=0A=
Thanks,=0A=
- Tyson=